1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) Paul Mackerras 1997. 4 * 5 * Updates for PPC64 by Todd Inglett, Dave Engebretsen & Peter Bergner. 6 */ 7 #include <stdarg.h> 8 #include <stddef.h> 9 #include "elf.h" 10 #include "page.h" 11 #include "string.h" 12 #include "stdio.h" 13 #include "ops.h" 14 #include "reg.h" 15 16 struct addr_range { 17 void *addr; 18 unsigned long size; 19 }; 20 21 #undef DEBUG 22 23 static struct addr_range prep_kernel(void) 24 { 25 char elfheader[256]; 26 unsigned char *vmlinuz_addr = (unsigned char *)_vmlinux_start; 27 unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start; 28 void *addr = 0; 29 struct elf_info ei; 30 long len; 31 int uncompressed_image = 0; 32 33 len = partial_decompress(vmlinuz_addr, vmlinuz_size, 34 elfheader, sizeof(elfheader), 0); 35 /* assume uncompressed data if -1 is returned */ 36 if (len == -1) { 37 uncompressed_image = 1; 38 memcpy(elfheader, vmlinuz_addr, sizeof(elfheader)); 39 printf("No valid compressed data found, assume uncompressed data\n\r"); 40 } 41 42 if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei)) 43 fatal("Error: not a valid PPC32 or PPC64 ELF file!\n\r"); 44 45 if (platform_ops.image_hdr) 46 platform_ops.image_hdr(elfheader); 47 48 /* We need to alloc the memsize: gzip will expand the kernel 49 * text/data, then possible rubbish we don't care about. But 50 * the kernel bss must be claimed (it will be zero'd by the 51 * kernel itself) 52 */ 53 printf("Allocating 0x%lx bytes for kernel...\n\r", ei.memsize); 54 55 if (platform_ops.vmlinux_alloc) { 56 addr = platform_ops.vmlinux_alloc(ei.memsize); 57 } else { 58 /* 59 * Check if the kernel image (without bss) would overwrite the 60 * bootwrapper. The device tree has been moved in fdt_init() 61 * to an area allocated with malloc() (somewhere past _end). 62 */ 63 if ((unsigned long)_start < ei.loadsize) 64 fatal("Insufficient memory for kernel at address 0!" 65 " (_start=%p, uncompressed size=%08lx)\n\r", 66 _start, ei.loadsize); 67 68 if ((unsigned long)_end < ei.memsize) 69 fatal("The final kernel image would overwrite the " 70 "device tree\n\r"); 71 } 72 73 if (uncompressed_image) { 74 memcpy(addr, vmlinuz_addr + ei.elfoffset, ei.loadsize); 75 printf("0x%lx bytes of uncompressed data copied\n\r", 76 ei.loadsize); 77 goto out; 78 } 79 80 /* Finally, decompress the kernel */ 81 printf("Decompressing (0x%p <- 0x%p:0x%p)...\n\r", addr, 82 vmlinuz_addr, vmlinuz_addr+vmlinuz_size); 83 84 len = partial_decompress(vmlinuz_addr, vmlinuz_size, 85 addr, ei.loadsize, ei.elfoffset); 86 87 if (len < 0) 88 fatal("Decompression failed with error code %ld\n\r", len); 89 90 if (len != ei.loadsize) 91 fatal("Decompression error: got 0x%lx bytes, expected 0x%lx.\n\r", 92 len, ei.loadsize); 93 94 printf("Done! Decompressed 0x%lx bytes\n\r", len); 95 out: 96 flush_cache(addr, ei.loadsize); 97 98 return (struct addr_range){addr, ei.memsize}; 99 } 100 101 static struct addr_range prep_initrd(struct addr_range vmlinux, void *chosen, 102 unsigned long initrd_addr, 103 unsigned long initrd_size) 104 { 105 /* If we have an image attached to us, it overrides anything 106 * supplied by the loader. */ 107 if (_initrd_end > _initrd_start) { 108 printf("Attached initrd image at 0x%p-0x%p\n\r", 109 _initrd_start, _initrd_end); 110 initrd_addr = (unsigned long)_initrd_start; 111 initrd_size = _initrd_end - _initrd_start; 112 } else if (initrd_size > 0) { 113 printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r", 114 initrd_addr, initrd_addr + initrd_size); 115 } 116 117 /* If there's no initrd at all, we're done */ 118 if (! initrd_size) 119 return (struct addr_range){0, 0}; 120 121 /* 122 * If the initrd is too low it will be clobbered when the 123 * kernel relocates to its final location. In this case, 124 * allocate a safer place and move it. 125 */ 126 if (initrd_addr < vmlinux.size) { 127 void *old_addr = (void *)initrd_addr; 128 129 printf("Allocating 0x%lx bytes for initrd ...\n\r", 130 initrd_size); 131 initrd_addr = (unsigned long)malloc(initrd_size); 132 if (! initrd_addr) 133 fatal("Can't allocate memory for initial " 134 "ramdisk !\n\r"); 135 printf("Relocating initrd 0x%lx <- 0x%p (0x%lx bytes)\n\r", 136 initrd_addr, old_addr, initrd_size); 137 memmove((void *)initrd_addr, old_addr, initrd_size); 138 } 139 140 printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr)); 141 142 /* Tell the kernel initrd address via device tree */ 143 setprop_val(chosen, "linux,initrd-start", (u32)(initrd_addr)); 144 setprop_val(chosen, "linux,initrd-end", (u32)(initrd_addr+initrd_size)); 145 146 return (struct addr_range){(void *)initrd_addr, initrd_size}; 147 } 148 149 /* A buffer that may be edited by tools operating on a zImage binary so as to 150 * edit the command line passed to vmlinux (by setting /chosen/bootargs). 151 * The buffer is put in it's own section so that tools may locate it easier. 152 */ 153 static char cmdline[BOOT_COMMAND_LINE_SIZE] 154 __attribute__((__section__("__builtin_cmdline"))); 155 156 static void prep_cmdline(void *chosen) 157 { 158 unsigned int getline_timeout = 5000; 159 int v; 160 int n; 161 162 /* Wait-for-input time */ 163 n = getprop(chosen, "linux,cmdline-timeout", &v, sizeof(v)); 164 if (n == sizeof(v)) 165 getline_timeout = v; 166 167 if (cmdline[0] == '\0') 168 getprop(chosen, "bootargs", cmdline, BOOT_COMMAND_LINE_SIZE-1); 169 170 printf("\n\rLinux/PowerPC load: %s", cmdline); 171 172 /* If possible, edit the command line */ 173 if (console_ops.edit_cmdline && getline_timeout) 174 console_ops.edit_cmdline(cmdline, BOOT_COMMAND_LINE_SIZE, getline_timeout); 175 176 printf("\n\r"); 177 178 /* Put the command line back into the devtree for the kernel */ 179 setprop_str(chosen, "bootargs", cmdline); 180 } 181 182 struct platform_ops platform_ops; 183 struct dt_ops dt_ops; 184 struct console_ops console_ops; 185 struct loader_info loader_info; 186 187 void start(void) 188 { 189 struct addr_range vmlinux, initrd; 190 kernel_entry_t kentry; 191 unsigned long ft_addr = 0; 192 void *chosen; 193 194 /* Do this first, because malloc() could clobber the loader's 195 * command line. Only use the loader command line if a 196 * built-in command line wasn't set by an external tool */ 197 if ((loader_info.cmdline_len > 0) && (cmdline[0] == '\0')) 198 memmove(cmdline, loader_info.cmdline, 199 min(loader_info.cmdline_len, BOOT_COMMAND_LINE_SIZE-1)); 200 201 if (console_ops.open && (console_ops.open() < 0)) 202 exit(); 203 if (platform_ops.fixups) 204 platform_ops.fixups(); 205 206 printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", 207 _start, get_sp()); 208 209 /* Ensure that the device tree has a /chosen node */ 210 chosen = finddevice("/chosen"); 211 if (!chosen) 212 chosen = create_node(NULL, "chosen"); 213 214 vmlinux = prep_kernel(); 215 initrd = prep_initrd(vmlinux, chosen, 216 loader_info.initrd_addr, loader_info.initrd_size); 217 prep_cmdline(chosen); 218 219 printf("Finalizing device tree..."); 220 if (dt_ops.finalize) 221 ft_addr = dt_ops.finalize(); 222 if (ft_addr) 223 printf(" flat tree at 0x%lx\n\r", ft_addr); 224 else 225 printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr); 226 227 if (console_ops.close) 228 console_ops.close(); 229 230 kentry = (kernel_entry_t) vmlinux.addr; 231 if (ft_addr) { 232 if(platform_ops.kentry) 233 platform_ops.kentry(ft_addr, vmlinux.addr); 234 else 235 kentry(ft_addr, 0, NULL); 236 } 237 else 238 kentry((unsigned long)initrd.addr, initrd.size, 239 loader_info.promptr); 240 241 /* console closed so printf in fatal below may not work */ 242 fatal("Error: Linux kernel returned to zImage boot wrapper!\n\r"); 243 } 244